Duchenne muscular dystrophy (DMD)

Duchenne muscular dystrophy (DMD) is a muscle wasting condition that causes progressive muscle weakness. It usually only affects boys and those assigned male at birth.

It’s caused by a lack of a protein called dystrophin. This causes muscle fibres to break down. They’re replaced by fibrous or fatty tissues that cause the muscle to gradually weaken.

DMD is a severe type of MD and often shortens life expectancy. Most people with DMD will reach adulthood. They are, however, more likely to die from heart or respiratory failure before or during their 30’s.

Symptoms of Duchenne muscular dystrophy

It’s unusual for symptoms to be present from birth. Often signs will appear between 1 and 2 years of age.

Someone with DMD might experience:

  • difficulties running, jumping and climbing stairs
  • difficulty getting up from the floor
  • a waddling gait (walking on their toes with an arched lower back)
  • difficulty walking as fast or as far as other children
  • a tendency to fall more than other children
  • learning and behavioural difficulties
  • learning to speak later than usual

Your child might find it difficult to stand up from a seated position. Your child might use the Gowers’ manoeuvre to stand up by:

  • facing the floor
  • placing their feet wide apart
  • lifting their bottom first
  • walking their hands from their knees to their thighs to a standing position

Speak to your GP if you or your child has symptoms of:

Speak to your GP if you or your child has symptoms of:

  • muscle weakness
  • mobility problems

Causes of DMD

DMD is a type of sex linked (X-linked) muscular dystrophy.

Males have one X and one Y chromosome (long threadlike structures of DNA). Females have two X chromosomes.

A sex linked disorder is caused by a mutation in a gene on the X chromosome.

As males only have one copy of the gene on the X chromosome, they’ll be affected if one of those genes is mutated.

Because females have 2 copies of the X chromosome, they’re less likely to develop an X-linked condition. This is because the healthy copy of the chromosome can usually compensate for (mask) the mutated version. This means that although females can still be affected by X-linked disorders, the symptoms are likely to be less severe.

Diagnosing DMD

There are different methods used to diagnose muscular dystrophy.

Diagnosis might involve:

  • investigating your symptoms
  • family history
  • physical exam
  • blood tests
  • electrical tests on the nerves and muscles
  • muscle biopsy (where a sample of tissue is removed for testing)

A blood test will normally be enough to confirm a diagnosis of DMD.

Read more about how muscular dystrophy will be diagnosed

Treatment of DMD

Treatment is available to help with many of the symptoms of Duchenne muscular dystrophy.


If you have Duchenne MD, corticosteroid medicine (steroids) can help improve your muscle strength and function. This can slow down the progress of muscle weakness.

Steroids are available in tablet or liquid form.

Read more about steroids and their possible side effects

Ataluren (Translarna)

Ataluren (Translarna) is used to treat some children with Duchenne MD that can still walk. It’s only effective for children with MD with a specific gene mutation.

Ataluren can help slow down the progress of muscle weakness. It’s prescribed as a sachet of granules which can be mixed into liquids or food like yoghurt and eaten.


A child with DMD could need a wheelchair by the time they’re 11 years old. At first, it might only be for long distances. Later it’s likely to be needed full time. At this stage, they might experience difficulties with other muscles like raising their arms above shoulder height.


Your child might benefit from splints or a spinal brace to help with their posture and mobility.

Corrective surgery

Duchenne MD can cause scoliosis. Surgery might be used to correct or to prevent scoliosis getting worse.

Heart problems

Many people with DMD develop dilated cardiomyopathy. This affects the heart muscles. The faulty gene also affects the heart muscles and causes the heart’s chambers to enlarge and the heart muscle to get thinner.

If you have Duchenne MD, you’ll have regular electrocardiograms (ECGs) to examine your heart rhythm. You’ll also need to have an echocardiogram. An MRI scan might be carried out to check for heart problems.

You’ll see a cardiologist (heart specialist) for further tests and monitoring.

The cardiologist will prescribe medication to help improve your heart function.

You might have a ICD (implantable cardioverter defibrillator) inserted to help with your heart function.

Last updated:
19 June 2024